Gun barrel manufacturing methods

ABSTRACT

A method of forming a gun barrel is disclosed that includes cold gas-dynamic spraying one or more coatings onto a mandrel. The method may also include heat treating the coating layer(s), contouring the outer coating layer, applying a ceramic top coating to the contoured outer coating layer of the gun barrel, and/or sealing the gun barrel with a liquid metal sealer. The method may also include removing the mandrel.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/182,578, entitled “Gun Barrel Manufacturing Methods” to Wright, whichwas filed on Jun. 14, 2016, now U.S. Pat. No. 9,695,489, which is acontinuation-in-part application of U.S. patent application Ser. No.14/942,694, entitled “Gun Barrel Manufacturing Methods” to Wright, whichwas filed on Nov. 16, 2015, now U.S. Pat. No. 9,365,930, which is acontinuation-in-part application of U.S. patent application Ser. No.14/155,093, entitled “Gun Barrel Manufacturing Methods” to Wright, whichwas filed on Jan. 14, 2014, now U.S. Pat. No. 9,186,712, whichapplication claims the benefit of the filing date of U.S. ProvisionalPatent Application 61/752,375, entitled “Gun Barrel ManufacturingMethods” to Wright, which was filed on Jan. 14, 2013, the contents ofall of which are all hereby incorporated by reference.

BACKGROUND 1. Technical Field

Aspects of this document relate generally to methods of manufacturinggun barrels.

2. Background Art

Regular use of guns often leads to the degradation of the aesthetic andperformance affecting characteristics of gun barrels.

SUMMARY

According to one aspect, a method of manufacturing a gun barrel mayinclude: cold gas-dynamic spraying a mandrel with a first coatingcomprising at least one of tungsten carbide, chrome carbide, ceramic,and any combination thereof; and cold gas-dynamic spraying the mandrelwith a second coating comprising at least one of an alloy, a superalloy,and any combination thereof.

Various implementations may include one or more of the following.

Cold gas-dynamic spraying a mandrel with a first coating may result in acoating thickness of between approximately 0.005 inches and 0.010inches.

Cold gas-dynamic spraying the mandrel with a second coating may includecold gas-dynamic spraying the mandrel with a second coating comprisingone of a nickel based, nickel-chromium based, and cobalt based alloy orsuperalloy.

Cold gas-dynamic spraying the mandrel with a second coating may resultin a coating thickness of between approximately 0.050 inches and 0.100inches.

The method may further include heat treating the first and secondcoatings.

The method may further include cold gas-dynamic spraying the mandrelwith a third coating comprising at least one of titanium powder,titanium alloy powder, aluminum powder, aluminum alloy powder,titanium-aluminum matrix powder, chromium powder, chromium alloy powder,cobalt powder, cobalt alloy powder, copper powder, copper alloy powder,iron powder, iron alloy powder, nickel powder, nickel alloy powder, andany combination thereof.

Cold gas-dynamic spraying the mandrel with a third coating may result ina combined coating thickness for the first, second, and third coatingsof between approximately 0.250 inches and 0.500 inches.

The method may further include heat treating the first, second, andthird coatings.

The method may further include one or more or all of the following:contouring the outer coating; spraying the outer coating with a ceramiccoating; and sealing the gun barrel with a liquid metal sealer.

The method may also include removing the mandrel.

According to another aspect, a method of manufacturing a gun barrel mayinclude: cold gas-dynamic spraying a mandrel with a first coatingcomprising at least one of an alloy, a superalloy, and any combinationthereof.

Various implementations may include one or more of the following.

Cold gas-dynamic spraying a mandrel with a first coating may includecold gas-dynamic spraying the mandrel with a coating comprising one of anickel based, nickel-chromium based, and cobalt based alloy orsuperalloy.

Cold gas-dynamic spraying a mandrel with a first coating may result in acoating thickness of between approximately 0.050 inches and 0.100inches.

The method may further include heat treating the coating.

The method may further include cold gas-dynamic spraying the mandrelwith a second coating comprising at least one of titanium powder,titanium alloy powder, aluminum powder, aluminum alloy powder,titanium-aluminum matrix powder, chromium powder, chromium alloy powder,cobalt powder, cobalt alloy powder, copper powder, copper alloy powder,iron powder, iron alloy powder, nickel powder, nickel alloy powder, andany combination thereof.

Cold gas-dynamic spraying the mandrel with a second coating may resultin a combined coating thickness for the first and second coatings ofbetween approximately 0.250 inches and 0.500 inches.

The method may further include heat treating the first and secondcoatings.

The method may further include one or more or all of the following:contouring the outer coating; spraying the outer coating with a ceramiccoating; and sealing the gun barrel with a liquid metal sealer.

The method may also include removing the mandrel.

According to still another aspect, a method of manufacturing a gunbarrel may include: cold gas-dynamic spraying the mandrel with a coatingcomprising at least one of titanium powder, titanium alloy powder,aluminum powder, aluminum alloy powder, titanium-aluminum matrix powder,chromium powder, chromium alloy powder, cobalt powder, cobalt alloypowder, copper powder, copper alloy powder, iron powder, iron alloypowder, nickel powder, nickel alloy powder, and any combination thereof.

Cold gas-dynamic spraying the mandrel with a coating may result in acoating thickness of between approximately 0.250 inches and 0.500inches.

The method may further include heat treating the coating.

The method may further include cold gas-dynamic spraying the mandrelwith an initial coating comprising at least one of tungsten carbide,chrome carbide, ceramic, and any combination thereof.

Cold gas-dynamic spraying the mandrel with an initial coating may resultin a coating thickness of between approximately 0.005 inches and 0.010inches.

The method may further include heat treating the two coatings.

The method may further include one or more or all of the following:contouring the outer coating; spraying the outer coating with a ceramiccoating; and sealing the gun barrel with a liquid metal sealer.

The method may also include removing the mandrel.

The foregoing and other aspects, features, and advantages will beapparent to those artisans of ordinary skill in the art from theDESCRIPTION and DRAWINGS, and from the CLAIMS.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will hereinafter be described in conjunction with theappended drawings, where like designations denote like elements, and:

FIG. 1 is a flowchart of a first implementation of a method ofmanufacturing a gun barrel;

FIG. 2 is a flowchart of a second implementation of a method ofmanufacturing a gun barrel;

FIG. 3 is a flowchart of a third implementation of a method ofmanufacturing a gun barrel;

FIG. 4 is a view of gun barrel with a portion of the gun barrel removedto allow a cross sectional view of the gun barrel;

FIG. 5 is a side view of a gun barrel liner coupled to a gun chamber;

FIG. 6 is a side view of a gun barrel liner and a gun chamber beforecoupling; and

FIG. 7 is a cross-sectional side view of a gun barrel liner coupled to agun chamber with one or more coatings applied to the gun barrel liner.

DESCRIPTION

This disclosure, its aspects and implementations, are not limited to thespecific components or assembly procedures disclosed herein. Manyadditional components and assembly procedures known in the artconsistent with the intended gun barrel and/or manufacture proceduresfor a gun barrel will become apparent for use with implementations ofgun barrels and methods of manufacture from this disclosure.Accordingly, for example, although particular gun barrels are disclosed,such gun barrels and implementing components may comprise any shape,size, style, type, model, version, measurement, concentration, material,quantity, and/or the like as is known in the art for such gun barrelsand implementing components, consistent with the intended operation ofgun barrels.

New gun barrels and methods of gun barrel manufacturing are disclosed inthis document. One or more implementations utilize powder metallurgy andmaterial (metal/ceramic) spray and other application techniques. Processimplementations described herein improve firearm performance andaccuracy. The gun barrels manufactures according to one or moreimplementations of this disclosure add lightweight strength, reducevibration, and control heat for a more accurate shooting gun barrel. Thevarious gun barrels may be created using procedures as added to andimproved upon through the procedures described here.

The following terminology will be used in accordance with thedefinitions and explanations set out below. Notwithstanding, otherterminology, definitions, and explanations may be found throughout thisdocument, as well.

As used in this document, “barrel” is a term used in its broadest senseand may refer to any core member (e.g., a tube) through which aprojectile (e.g., bullet) will be ultimately fired. Barrels may becomprised of any materials, shapes, sizes, styles, types, models,versions, classes, grades, measurements, weights, and the like. Barrelsmay be in any process state or form as well, such as barrel liners,barrel blanks, machined barrels, reduced diameter barrels, barrels builtup on mandrels, new barrels, used barrels, and the like. It is alsonoted that not all barrel manufacturers have/use the samecontours/profiles and the like of barrels, such that there can be anydifferent number of ways of classifying/categorizing them. Accordingly,contours may be classified by characteristics, such as Thin, Medium,Heavy, Straight, and the like for example. Contours may be classified bynumbers, such as Contour 1, Contour 2, Contour 3, and the like forexample. Contours may be classified by names, such as Featherweight,Lightweight, Lightweight Sporter, Sporter, Magnum Sporter, HeavySporter, Lightweight Varmint, Varmint, Heavy Varmint, Bull, Heavy Bull,Rimfire, Rimfire Target, Benchrest, Straight, Super Size, Light Palma,Palma, Heavy Palma, Remington, and the like for example. Contours maynot have a classification and may be completely custom for example.Contours may be classified by any combination of characteristics,numbers, names, and the like, such as 3 Sporter, 4 Magnum Sporter, 4.1Magnum Sporter, 5 Lt Varmint Sporter, 5.5 Med Varmint Sporter, 5.75 HvyVarmint Sporter, 6 Light Target, 7.1 Light Varmint, 7.2 Light Varmint,7.4 Light Varmint, 7.5 Light Varmint, 7.6 Light Varmint, 7.7 HeavyVarmint, 7.8 Max Heavy Varmint, 7.9 1000 Yard, 8 Heavy Bull, 9 RimfireTarget, 10 Hunter, 12 Palma Std, 12.2 Palma Light, 12.4 Palma Heavy,Special Large, and the like for example. Additionally, barrelcontours/profiles for different types of firearm platforms can havedifferent names and/or other forms of classification/categorization. Forexample, there can be Bolt Action Contours (e.g., Match/VarmintContours, Sporter Contours, Palma Contours, Straight Contours, and thelike), M1 Garand, M1A/M14, M1903 Contours (e.g., GI Pattern, HeavyPattern, Med. Bush Pattern, Med. Weight Pattern, Heavy Pattern, M1903,M1903-A3, and the like), AR-15 Contours (e.g., Lightweight/Pencil,M4/Government, Heavy, Carbine Pre Ban, Mid Weight, H-Bar, Varmatch, andthe like), AR-10 Contours (e.g., AR10/DPMS, M110, and the like), and thelike.

In the following description, it is to be understood that otherimplementations may be utilized, and structural, as well as procedural,changes may be made without departing from the scope of this document.As a matter of convenience, various components will be described usingexemplary materials, sizes, shapes, dimensions, and the like. However,this document is not limited to the stated examples and otherconfigurations are possible and within the teachings of the presentdisclosure.

In one or more implementations, an improved or enhanced gun barrel maybe manufactured from a previously existing gun barrel. The previouslyexisting gun barrel may be a new or used gun barrel. FIG. 1 depicts anon-limiting flowchart of one implementation of manufacturing a gunbarrel from a previously existing gun barrel. It is to be understoodthat various implementations may not include each of the steps shown inthe flowchart of FIG. 1 and the order of the steps shown in FIG. 1 isnot limiting. That is, in other implementations, the steps may beperformed in an order different than that shown in FIG. 1 or any or allof steps 11, 12, and 13 for example may not be included withoutdeparting from the scope of this disclosure.

In one or more implementations, a method for manufacturing a gun barrelcomprises machining a gun barrel (step 11). Again, this step is optionalas one could start directly with step 12 or step 13 depending on thestarting barrel for example.

Machining the gun barrel may comprise any methods or mechanisms formachining a gun barrel previously known in the art. According to someaspects, machining the gun barrel comprises machining an existing gunbarrel to a desired wall the thickness. The desired wall thickness mayvary according to the caliber or type of gun for which the gun barrelwill be used. According to another aspect, the wall thickness may remainrelatively constant, but the actual diameter of the gun barrel will varydependent upon the caliber of the gun. The wall thickness aftermachining is within acceptable safe pressure limits specific to the gunfor which barrel will be used.

In one or more implementations, a method for manufacturing a gun barrelfurther comprises machining a threaded or muzzle end of the gun barrel(step 12). Again, this step is optional as one could start directly withstep 9. Machining a threaded end of the gun barrel, according to someaspects, prepares or allows for coupling of at least one of a sleeve, aknurled nut cap, or a recoil brake to the threaded end of the gun barrel(step 13). The sleeve, knurled nut cap, or recoil brake may individuallyor in combination with one another provide a dam or barrier to the spraythat is applied to the gun at a later time. A tool or tape may becoupled to the other end of the gun barrel while the coatings aresprayed on the gun barrel.

One or more implementations of a method of manufacturing a gun barrelfurther comprise spraying the gun barrel with a first or bonding coating(step 9). According to some aspects, spraying the gun barrel with abonding coating comprises spraying the gun barrel with a second hard,dense coating to form a bonding layer. The bonding coating is typicallysprayed on the gun barrel with a thermal spraying technique, such as butnot limited to plasma spraying, HVOF, wire arc spraying, flame spraying,cold spraying, or any other technique for applying or depositing metaland/or ceramic coatings to the gun barrel.

The bonding coating forms a metallurgical bond to the gun barrel. Thehard, dense coating of the bonding coating may comprise any compoundscommonly known in the art. The bonding coating may comprise a materialthat work hardens. The bonding coating forms an integral strong basematerial that sustains pressures and fatigue values commonly associatedwith the combustion of powder and gasses from firing a live round andpropelling the projectile (e.g. bullet) down the gun barrel to exit as ashot.

Some examples of materials are alloys and superalloys. An alloy is amixture of metals or a mixture of a metal and another element. An alloymay be a solid solution of metal elements (a single phase) or a mixtureof metallic phases (two or more solutions). Virtually any alloy may beemployed. For the exemplary purposes of this disclosure, some alloysthat are suitable for manufacturing methods disclosed here may be Alloysof aluminum, Alloys of chromium, Alloys of cobalt, Alloys of copper,Alloys of iron, Alloys of nickel, Alloys of titanium, and the like. Somealloys are nickel based, nickel-chromium based, cobalt based, zincbased, and the like. For example, a range copper-zinc alloys may beemployed with differing combinations of properties, including strength,machinability, wear-resistance, hardness, color, thermal conductivity,and corrosion-resistance. A superalloy, or high-performance alloy, is analloy that exhibits several key characteristics: excellent mechanicalstrength, resistance to thermal creep deformation, good surfacestability and resistance to corrosion or oxidation (oxidation orcorrosion resistance may be provided by elements such as aluminum andchromium for example). Some superalloys are nickel based,nickel-chromium based, cobalt based, and the like. Examples ofsuperalloys are Hastelloy, Inconel (a family of austenitenickel-chromium-based superalloys), Waspaloy, Rene alloys, Haynesalloys, Incoloy, MP98T, TMS alloys, CMSX single crystal alloys, and thelike.

Other materials may be metallic/ceramic materials, hafnium diboride, andthe like. Even other materials may be any equivalents or combinations ofany of the foregoing materials.

According to one aspect, the bonding coating is between approximately0.005 inches and 0.010 inches thick after sprayed application to the gunbarrel.

In one or more implementations, a method of manufacturing a gun barrelfurther comprises cold spraying gun barrel (step 14). More particularly,cold spraying the gun barrel may comprise cold gas-dynamic spraying thegun barrel with metal powder to form an outer layer. In one or moreimplementations, the metal powder comprises titanium powder, titaniumalloy powder, aluminum powder, aluminum alloy powder, titanium-aluminummatrix powder, chromium powder, chromium alloy powder, cobalt powder,cobalt alloy powder, a copper powder, a copper alloy powder, ironpowder, iron alloy powder, nickel powder, nickel alloy powder, and anycombination thereof. Generally, the metal powder cold sprayed onto thegun barrel will be thick enough for a final machining of the gun barrelto a specified gun barrel contour. According to an aspect, the thicknessof the gun barrel and the outer layer after spraying the gun barrel withthe metal powder is between approximately 0.250 inches and 0.500 inchesthick. More particularly, the thickness of the gun barrel and the outerlayer after spraying the gun barrel with the metal powder is betweenapproximately 0.300 inches and 0.500 inches thick.

Cold gas-dynamic spraying is highly advantageous to other methods ofapplying metals to a gun barrel. For example, cold gas-dynamic sprayinga gun barrel with one or more of the listed metal powders fills andgives metallic strength to the gun barrel, resulting in a light-weightand relatively strong metal filler. Moreover, cold gas-dynamic sprayingof the metal powder allows the metal powder to have metallurgical bondto the surface of the gun barrel as a solid state material with no heataffected zone, phase change, or oxide contamination. The added value ofthis material adds light-weight strength, reduces vibration, andcontrols heat for a more accurate shooting gun barrel.

One or more implementations of a method for manufacturing a gun barrelcomprise contouring the outer layer sprayed on the gun barrel (step 15).Contouring the outer layer may comprise machining, grinding, or anyother method of contouring otherwise known in the art. In one or moreimplementations, the outer layer sprayed on the gun barrel is contouredto a specified barrel contour. According to some aspects, a method formanufacturing a gun barrel comprises polishing the gun barrel (step 16).Polishing the gun barrel is typically performed after the gun barrel iscontoured. Sand paper comprising between approximately 100 and 800 gritmay be utilized to polish the gun barrel.

One or more implementations of a method for manufacturing a gun barrelcomprise applying a ceramic top coating to the gun barrel (step 17).According to some aspects, the ceramic top coating is applied to the gunbarrel after the metal powder has been sprayed on the gun barrel andbefore the gun barrel is sealed with a seal coating. More particularly,the ceramic top coating may be applied to the gun barrel after the gunbarrel is contoured and before the gun barrel is sealed with a sealcoating. The ceramic top coating typically adds aesthetic and mechanicalproperties, such as vibration and heat control, to the gun barrel.

The ceramic top coating may be applied to a desired thickness. In one ormore implementations, the ceramic top coating is applied to a thicknessof between approximately 0.015 inches and 0.030 inches. Application ofthe ceramic top coating may be through any application method ormechanism known in the art. In one, non-limiting implementation, theceramic top coating is applied by plasma flame spraying the ceramic topcoating on the gun barrel.

One or more implementations of manufacturing a gun barrel furthercomprise sealing the gun barrel (step 18). According to some aspects,sealing the gun barrel comprises seal coating the exterior of the gunbarrel with a liquid metal sealer. The liquid metal sealer may be of aphenolic base, such as those liquid metal sealers supplied by Metco(Metcoseal AP or BP) or Dictol Sealer. In other implementations, anyliquid metal sealer known in the art may be utilized.

One or more implementations of manufacturing a gun barrel furthercomprise marking the gun barrel (step 19). Marking the gun barreltypically comprises marking the gun barrel with identifying marks thatallow a user to identify at least one of the model and caliber of theinside barrel. Marking may further comprise marking the gun barrel witha brand identifying mark, such as Gunwright™. Marking may be done with achemical, mechanical, laser, or any other marking mechanism known in theart.

Also contemplated as part of this disclosure is a method ofmanufacturing or fabricating a new gun barrel. A new gun barrel may bemanufactured or completely fabricated from powder metallurgy and metalspray techniques. In general, one or more methods of manufacturing a newgun barrel uses a material coating process that applies coatings upon amandrel or other sacrificial base that copies the caliber diameter withrifling and shell sporting arms and ammunition manufacturers' institute(SAAMI) dimensions in reverse. FIG. 2 depicts a non-limiting flowchartof one implementation of manufacturing or fabricating a new gun barrel.It is to be understood that various implementations may not include eachof the steps shown in the flowchart of FIG. 2 and the order of the stepsshown in FIG. 2 is not limiting. For example, in other implementations,the steps may be performed in an order different than that shown in FIG.2 without departing from the scope of this disclosure.

One or more implementations of manufacturing a gun barrel comprisepreparing a mandrel (step 21). Preparing a mandrel typically comprisesproviding a mandrel or modifying a mandrel such that mandrel is sizedsubstantially equal to the bore of a specified gun barrel. The mandrelmay comprise a sacrificial rod and shell representing the reverse of theinside of a barrel. According to some aspects, the mandrel isconstructed by one or more of machining, grinding, or electricaldischarge machining (EDM) until the mandrel is sized substantially equalto the bore and includes, in some implementations, the desired rifling.

One or more implementations of a method of manufacturing a gun barrelcomprise spraying the mandrel with a first coating (step 22). Accordingto some aspects, spraying the mandrel with a first coating comprisesspraying the mandrel with a hard, dense coating that includes at leastone of tungsten carbide, chrome carbide, or ceramic. According to otheraspects, the hard, dense coating of the first coating may comprise anycompounds commonly known in the art. The first coating is typicallysprayed on the mandrel with a thermal spraying technique, such as butnot limited to plasma spraying, high velocity oxygen fuel (HVOF), flamespraying, cold spraying, or any other technique for applying ordepositing metal and/or ceramic coatings to the mandrel to form anintegral hard surface. More particularly, rifling and/or SAAMI shelldimensions may be imprinted on the interior of the first coating afterapplication of the first coating to the mandrel. According to oneaspect, the first coating is approximately 0.010 inches thick aftersprayed application to the mandrel.

One or more implementations of a method of manufacturing a gun barrelfurther comprise spraying the mandrel with a second coating (step 23).According to some aspects, spraying the mandrel with a second coatingcomprises spraying the mandrel with a second hard, dense coating afterapplication of the first coating. In other implementations, the secondcoating may be sprayed directly on the mandrel. The second coating istypically sprayed on the mandrel with a thermal spraying technique, suchas but not limited to plasma spraying, HVOF, flame spraying, coldspraying, or any other technique for applying or depositing metal and/orceramic coatings to the mandrel.

The second bonding coating forms a metallurgical bond to the firstcoating. The hard, dense coating of the bonding coating may comprise anycompounds commonly known in the art. The bonding coating may comprise amaterial that work hardens. The bonding coating forms an integral strongbase material that sustains pressures and fatigue values commonlyassociated with the combustion of powder and gasses from firing a liveround and propelling the projectile (e.g. bullet) down the gun barrel toexit as a shot.

Some examples of materials are alloys and superalloys. An alloy is amixture of metals or a mixture of a metal and another element. An alloymay be a solid solution of metal elements (a single phase) or a mixtureof metallic phases (two or more solutions). Virtually any alloy may beemployed. For the exemplary purposes of this disclosure, some alloysthat are suitable for manufacturing methods disclosed here may be Alloysof aluminum, Alloys of chromium, Alloys of cobalt, Alloys of copper,Alloys of iron, Alloys of nickel, Alloys of titanium, and the like. Somealloys are nickel based, nickel-chromium based, cobalt based, zincbased, and the like. For example, a range copper-zinc alloys may beemployed with differing combinations of properties, including strength,machinability, wear-resistance, hardness, color, thermal conductivity,and corrosion-resistance. A superalloy, or high-performance alloy, is analloy that exhibits several key characteristics: excellent mechanicalstrength, resistance to thermal creep deformation, good surfacestability and resistance to corrosion or oxidation (oxidation orcorrosion resistance may be provided by elements such as aluminum andchromium for example). Some superalloys are nickel based,nickel-chromium based, cobalt based, and the like. Examples ofsuperalloys are Hastelloy, Inconel (a family of austenitenickel-chromium-based superalloys), Waspaloy, Rene alloys, Haynesalloys, Incoloy, MP98T, TMS alloys, CMSX single crystal alloys, and thelike.

Other materials may be metallic/ceramic materials, hafnium diboride, andthe like. Even other materials may be any equivalents or combinations ofany of the foregoing materials.

According to one aspect, the second coating is between approximately0.050 inches and 0.100 inches thick after sprayed application to themandrel.

In one or more implementations, a method of manufacturing a gun barrelfurther comprises cold spraying the mandrel with a third coating (step24). More particularly, cold spraying the mandrel may comprise coldgas-dynamic spraying the mandrel after application of one or both of thefirst and second coatings with a third coating comprising a metal powderto form a metal layer. In one or more implementations, the metal powdercomprises titanium powder, titanium alloy powder, aluminum powder,aluminum alloy powder, titanium-aluminum matrix powder, chromium powder,chromium alloy powder, cobalt powder, cobalt alloy powder, copperpowder, copper alloy powder, copper powder, copper alloy powder, ironpowder, iron alloy powder, nickel powder, nickel alloy powder, and anycombination thereof. Generally, the metal powder cold sprayed onto themandrel will be thick enough for a final machining of the fabricated gunbarrel to a specified gun barrel contour. According to an aspect, thethickness of the first, second, and third coatings after spraying themandrel with the metal powder is between approximately 0.250 inches and0.500 inches thick. More particularly, the thickness of the first,second, and third coatings after spraying the mandrel with the metalpowder is between approximately 0.300 inches and 0.500 inches thick.

Similar to previous implementations, cold gas-dynamic spraying is highlyadvantageous to other methods of applying metals to a fabricated gunbarrel. For example, cold gas-dynamic spraying a mandrel with one ormore of the listed metal powders fills and gives metallic strength tothe fabricated gun barrel, resulting in a light-weight and relativelystrong metal filler. Moreover, cold gas-dynamic spraying of the metalpowder allows the metal powder to have metallurgical bond to the surfaceof the second coating as a solid state material with no heat affectedzone, phase change, or oxide contamination. The added value of thismaterial adds light-weight strength, reduces vibration, and controlsheat for a more accurate shooting gun barrel.

One or more implementations of manufacturing a gun barrel furthercomprise heat treating at least one of the first, second, and thirdcoatings (step 25). Heat treating at least one of the first, second, andthird coatings typically comprises heat treating or annealing therespective coating(s) at applicable temperatures to normalize thematerial as applied. Heat treatment temperature ranges may be betweenapproximately −300° C. and 1500° C. According to various aspects, heattreating of the one or more coatings may be performed after machining ofthe coatings or, alternatively, after an initial machining and before afinal machining of the coatings.

One or more implementations of manufacturing a gun barrel furthercomprise contouring the sprayed layer of the sprayed coatings (step 26).Contouring the sprayed layer may comprise machining, grinding, or anyother method of contouring otherwise known in the art. The sprayed layertypically comprises the third coating. In one or more implementations,the sprayed layer sprayed on the fabricated gun barrel is contoured to aspecified barrel contour.

One or more implementations of manufacturing a gun barrel furthercomprise removing the mandrel from the first, second, and third coatings(step 27). Removing the mandrel from the sprayed first, second, and/orthird coatings is typically done via mechanical, chemical, or any otherremoval technique or mechanism known in the art.

According to some aspects, a method for manufacturing a gun barrelcomprises polishing the sprayed layer of the fabricated gun barrel (step28). Polishing the sprayed is typically performed after the sprayedlayer is contoured. Sand paper comprising between approximately 100 and800 grit may be utilized to polish the gun barrel.

One or more implementations of a method for manufacturing a gun barrelcomprise applying a ceramic top coating to the third coating of thefabricate gun barrel (step 29). According to some aspects, the ceramictop coating is applied to the third coating of the fabricated gun barrelafter the metal powder has been sprayed on the gun barrel and before thegun barrel is sealed with a seal coating. More particularly, the ceramictop coating may be applied to the gun barrel after the gun barrel iscontoured and before the gun barrel is sealed with a seal coating. Theceramic top coating typically adds aesthetic and mechanical properties,such as vibration and heat control, to the gun barrel.

The ceramic top coating may be applied to a desired thickness. In one ormore implementations, the ceramic top coating is applied to a thicknessof between approximately 0.015 inches and 0.030 inches. Application ofthe ceramic top coating may be through any application method ormechanism known in the art. In one, non-limiting implementation, theceramic top coating is applied by plasma flame spraying the ceramic topcoating on the gun barrel.

One or more implementations of manufacturing a gun barrel furthercomprise sealing the third coating of the fabricated gun barrel (step30). According to some aspects, sealing the third coating of thefabricated gun barrel comprises seal coating the exterior of the thirdcoating of the fabricated gun barrel with a liquid metal sealer. Theliquid metal sealer may be of a phenolic base, such as those liquidmetal sealers supplied by Metco (Metcoseal AP or BP) or Dictol Sealer.In other implementations, any liquid metal sealer known in the art maybe utilized.

One or more implementations of manufacturing a gun barrel furthercomprise marking the fabricated gun barrel (step 20). Marking the gunbarrel typically comprises marking the fabricated gun barrel withidentifying marks that allow a user to identify at least one of themodel and caliber of the inside barrel. Marking may further comprisemarking the fabricated gun barrel with a brand identifying mark, such asGunwright material. Marking may be done with a chemical, mechanical,laser, or any other marking mechanism known in the art.

Also contemplated as part of this disclosure are other methods ofmanufacturing or fabricating a new gun barrel. A new gun barrel may bemanufactured or completely fabricated from powder metallurgy and metalspray techniques. In general, one or more methods of manufacturing a newgun barrel uses a material coating process that applies one or morecoatings to a barrel comprising a gun barrel liner that copies thecaliber diameter with rifling and SAAMI dimensions in reverse.

FIG. 3 depicts a non-limiting flowchart of one implementation ofmanufacturing or fabricating a new gun barrel. It is to be understoodthat various implementations may not include each of the steps shown inthe flowchart of FIG. 3 and the order of the steps shown in FIG. 3 isnot limiting. That is, in other implementations, the steps may beperformed in an order different than that shown in FIG. 3 and step 31may not be included without departing from the scope of this disclosure.The barrel may comprise any gun barrel liner known in the art and,according to some aspects, comprise rifling and/or SAAMI dimensions.

One or more implementations of a method of manufacturing a gun barrelcomprise spraying a gun barrel liner with a first coating (step 31).Again, step 31 often is not included and the method usually begins withstep 32. Spraying the gun barrel liner with a first coating typicallycomprises spraying the gun barrel liner with a hard, dense coating thatincludes at least one of tungsten carbide, chrome carbide, or ceramic.According to other aspects, the hard, dense coating of the first coatingmay comprise any compounds commonly known in the art. The first coatingis typically sprayed on the gun barrel liner with a thermal sprayingtechnique, such as but not limited to plasma spraying, HVOF, flamespraying, cold spraying, or any other technique for applying ordepositing metal and/or ceramic coatings to the gun barrel liner to forman integral hard surface. According to one aspect, the first coating isapproximately 0.010 inches thick after sprayed application to the gunbarrel liner.

One or more implementations of a method of manufacturing a gun barrelfurther comprise spraying the gun barrel liner with a second coating(step 32). According to some implementations, spraying the gun barrelliner with a second coating comprises spraying the gun barrel liner witha second hard, dense coating after application of the first coating. Inmost implementations, however, the second coating may be sprayeddirectly on the gun barrel liner without including a first coating. Thesecond coating is typically sprayed on the gun barrel liner with athermal spraying technique, such as but not limited to plasma spraying,HVOF, flame spraying, cold spraying, or any other technique for applyingor depositing metal and/or ceramic coatings to the gun barrel liner.

The second coating forms a metallurgical bond to the first coatingand/or the gun barrel liner. The hard, dense coating of the second orbonding coating may comprise any compounds commonly known in the art.The bonding coating may comprise a material that work hardens. Thebonding coating forms an integral strong base material that sustainspressures and fatigue values commonly associated with the combustion ofpowder and gasses from firing a life round and propelling the projectile(e.g. bullet) down the gun barrel to exit as a shot.

Some examples of materials are alloys and superalloys. An alloy is amixture of metals or a mixture of a metal and another element. An alloymay be a solid solution of metal elements (a single phase) or a mixtureof metallic phases (two or more solutions). Virtually any alloy may beemployed. For the exemplary purposes of this disclosure, some alloysthat are suitable for manufacturing methods disclosed here may be Alloysof aluminum, Alloys of chromium, Alloys of cobalt, Alloys of copper,Alloys of iron, Alloys of nickel, Alloys of titanium, and the like. Somealloys are nickel based, nickel-chromium based, cobalt based, zincbased, and the like. For example, a range copper-zinc alloys may beemployed with differing combinations of properties, including strength,machinability, wear-resistance, hardness, color, thermal conductivity,and corrosion-resistance. A superalloy, or high-performance alloy, is analloy that exhibits several key characteristics: excellent mechanicalstrength, resistance to thermal creep deformation, good surfacestability and resistance to corrosion or oxidation (oxidation orcorrosion resistance may be provided by elements such as aluminum andchromium for example). Some superalloys are nickel based,nickel-chromium based, cobalt based, and the like. Examples ofsuperalloys are Hastelloy, Inconel (a family of austenitenickel-chromium-based superalloys), Waspaloy, Rene alloys, Haynesalloys, Incoloy, MP98T, TMS alloys, CMSX single crystal alloys, and thelike.

Other materials may be metallic/ceramic materials, hafnium diboride, andthe like. Even other materials may be any equivalents or combinations ofany of the foregoing materials.

According to one aspect, the second coating is between approximately0.050 inches and 0.100 inches thick after sprayed application to the gunbarrel liner.

In one or more implementations, a method of manufacturing a gun barrelfurther comprises cold spraying the gun barrel liner with a thirdcoating (step 33). More particularly, cold spraying the gun barrel linermay comprise cold gas-dynamic spraying the gun barrel liner afterapplication of one or both of the first and second coatings with a thirdcoating comprising a metal powder to form a metal layer. In one or moreimplementations, the metal powder comprises titanium powder, titaniumalloy powder, aluminum powder, aluminum alloy powder, titanium-aluminummatrix powder, chromium powder, chromium alloy powder, cobalt powder,cobalt alloy powder, copper powder, copper alloy powder, iron powder,iron alloy powder, nickel powder, nickel alloy powder, and anycombination thereof. Generally, the metal powder cold sprayed onto thegun barrel liner will be thick enough for a final machining of thefabricated gun barrel to a specified gun barrel contour. According to anaspect, the thickness of the first, second, and third coatings afterspraying the gun barrel liner with the metal powder is betweenapproximately 0.250 inches and 0.500 inches thick. More particularly,the thickness of the first, second, and third after spraying the gunbarrel liner with the metal powder is between approximately 0.300 inchesand 0.500 inches thick.

Similar to previous implementations, cold gas-dynamic spraying is highlyadvantageous to other methods of applying metals to a fabricated gunbarrel. For example, cold gas-dynamic spraying a gun barrel liner withone or more of the listed metal powders fills and gives metallicstrength to the fabricated gun barrel, resulting in a light-weight andrelatively strong metal filler. Moreover, cold gas-dynamic spraying ofthe metal powder allows the metal powder to have metallurgical bond tothe surface of the second coating as a solid state material with no heataffected zone, phase change, or oxide contamination. The added value ofthis material adds light-weight strength, reduces vibration, andcontrols heat for a more accurate shooting gun barrel.

One or more implementations of manufacturing a gun barrel furthercomprise heat treating at least one of the first, second, and thirdcoatings (step 34). Heat treating at least one of the first, second, andthird coatings typically comprises heat treating or annealing therespective coating(s) at applicable temperatures to normalize thematerial as applied. Heat treatment temperature ranges may be betweenapproximately −300° C. and 1500° C. According to various aspects, heattreating of the one or more coatings may be performed after machining ofthe coatings or, alternatively, after an initial machining and before afinal machining of the coatings.

One or more implementations of manufacturing a gun barrel furthercomprise contouring the sprayed layer of the sprayed coatings (step 35).Contouring the sprayed layer may comprise machining, grinding, or anyother method of contouring otherwise known in the art. The sprayed layertypically comprises the third coating. In one or more implementations,the sprayed layer sprayed on the fabricated gun barrel is contoured to aspecified barrel contour.

According to some aspects, a method for manufacturing a gun barrelcomprises polishing the sprayed layer of the fabricated gun barrel (step36). Polishing the sprayed is typically performed after the sprayedlayer is contoured. Sand paper comprising between approximately 100 and800 grit may be utilized to polish the fabricated gun barrel.

One or more implementations of a method for manufacturing a gun barrelcomprise applying a ceramic top coating to the third coating of thefabricate gun barrel (step 37). According to some aspects, the ceramictop coating is applied to the third coating of the fabricated gun barrelafter the metal powder has been sprayed on the gun barrel and before thegun barrel is sealed with a seal coating. More particularly, the ceramictop coating may be applied to the fabricated gun barrel after thesprayed layer is contoured and before the one or more coatings aresealed with a seal coating. The ceramic top coating typically addsaesthetic and mechanical properties, such as vibration and heat control,to the gun barrel.

The ceramic top coating may be applied to a desired thickness. In one ormore implementations, the ceramic top coating is applied to a thicknessof between approximately 0.015 inches and 0.030 inches. Application ofthe ceramic top coating may be through any application method ormechanism known in the art. In one, non-limiting implementation, theceramic top coating is applied by plasma flame spraying the ceramic topcoating on the fabricated gun barrel.

One or more implementations of manufacturing a gun barrel furthercomprise sealing the third coating of the fabricated gun barrel (step38). According to some aspects, sealing the third coating of thefabricated gun barrel comprises seal coating the exterior of the thirdcoating of the fabricated gun barrel with a liquid metal sealer. Theliquid metal sealer may be of a phenolic base, such as those liquidmetal sealers supplied by Metco (Metcoseal AP or BP) or Dictol Sealer.In other implementations, any liquid metal sealer known in the art maybe utilized.

One or more implementations of manufacturing a gun barrel furthercomprise marking the fabricated gun barrel (step 39). Marking the gunbarrel typically comprises marking the fabricated gun barrel withidentifying marks that allow a user to identify at least one of themodel and caliber of the inside barrel. Marking may further comprisemarking the fabricated gun barrel with a brand identifying mark, such asGunwright material. Marking may be done with a chemical, mechanical,laser, or any other marking mechanism known in the art.

FIG. 4 depicts a view of a non-limiting manufactured gun barrel 1 formedaccording to one or more implementations of the methods disclosedherein, with a portion of the gun barrel 1 removed to allow a crosssectional view of the gun barrel 1. The gun barrel 1 depicted in FIG. 4may comprise any gun barrel in the art without departing from the scopeof this disclosure. But for exemplary purposes, in the non-limitingexample shown in FIG. 4, the gun barrel 1 an original gun barrel 3surrounding the bore 2 of the gun barrel. The manufactured gun barrel 1further comprises a bonding coating 4 adjacent the original gun barrel3. Adjacent the bonding coating 4 opposite the original gun barrel 3 isan outer layer 5. The bonding coating 4 and outer layer 5 may be formedof any of the materials described above in relation to one or moreimplementations associated with the flowchart of FIG. 1. Similarly, thethickness of the original gun barrel 3, the bonding coating 4, and theouter layer 5 may comprise any of the thicknesses described in otherimplementations presented herein.

Although gun barrels manufactured according to the variousimplementations described in relation to FIGS. 2 and 3 are not expresslyshown, some gun barrels manufactured according to these implementationsare similar to that shown in FIG. 4. For example, one or more gunbarrels manufactured according to implementations of methods related toFIG. 2 comprise a mandrel shaped sized and shaped similar to the bore 2depicted in FIG. 4 or the bore of any gun barrel known in the art.Furthermore, one or more gun barrels manufactured accordingimplementations of methods related to FIG. 2 may comprise a firstcoating positioned similar to the original gun barrel 3, a secondcoating positioned similar to the bonding coating 4, and a third coatingpositioned similar to the outer layer 5 of FIG. 4. Dimensions of thesecoatings are according to those described in relation to FIG. 2.

Similarly, one or more gun barrels manufactured according toimplementations of methods related to FIG. 3 comprise a gun barrel linersized and shaped similar to the bore 2 depicted in FIG. 4 or the bore ofany gun barrel known in the art. Furthermore, one or more gun barrelsmanufactured according to implementations of methods related to FIG. 3may comprise a first coating positioned similar to the original gunbarrel 3, a second coating positioned similar to the bonding coating 4,and a third coating positioned similar the outer layer 5 of FIG. 4.Dimensions of these coatings are according to those described inrelation to FIG. 3.

Also contemplated in this disclosure are various systems and methods formanufacturing a gun barrel utilizing a barrel that comprises a gunbarrel liner 50. FIGS. 5-7 depict various views of stages during stillanother non-limiting implementation of systems and methods formanufacturing or fabricating a gun barrel. FIG. 6, for example, depictsa cross section view of a gun barrel liner 50 separated from a gunchamber 70 before coupling. FIG. 5 shows a side view of a gun barrelliner 50 coupled to a gun chamber 70 with coupling material 56(described in greater detail below) before additional layers have beenapplied to the gun barrel liner 50. FIG. 7 is a cross sectional view ofFIG. 5, with the additional of one or more coatings that shall bedescribed in greater detail below or elsewhere in this document. It isto be understood that various implementations may not include each ofthe steps described below and shown in the FIGS. 5-7 and the order ofthe steps described is not limiting. That is, in other implementations,the steps may be performed in an order different than that described andshown or applying a bond coating for example may not be included (justapplying a top coating) without departing from the scope of thisdisclosure.

In some non-limiting implementations, a method of manufacturing a gunbarrel, comprises threading an outer surface 52 of a gun barrel liner 50proximate a first end 51 of the gun barrel liner 50 to form malethreading 54. A method may further comprise threadedly coupling thefirst end 51 of the gun barrel liner 51 to a gun chamber 70. A methodmay still further comprise fixedly coupling the gun barrel liner 50 tothe gun chamber 70 with coupling material 56. Finally, a method ofmanufacturing a gun barrel may comprise applying one or more coatings tothe gun barrel liner 50.

According to some aspects and prior to applying one or more coatings, amethod of forming a gun barrel may further comprise threading an innersurface 71 of the gun chamber 70 to form female threading 72complementary to the threading 54 of the gun barrel liner 50. Fixedlycoupling the gun barrel liner 50 to the gun chamber 70 with couplingmaterial 56 may comprise at least one of tack welding, soldering, orbrazing the gun barrel liner and the gun chamber.

According to some aspects, applying one or more coatings to the gunbarrel liner 50 may comprise spraying the outer surface 52 of gun barrelliner 50 with a bond coating 62. The bond coating 62 may comprise anickel based alloy or superalloy or any of the other applicable bondcoating materials described previously in this document. Spraying thegun barrel liner 50 with coating 62 may comprise thermaly spraying (e.g.plasma spraying or high velocity oxygen fuel spraying) the gun barrelliner 50 with the coating 62 until the coating 62 is betweenapproximately 0.050 inches and 0.100 inches thick.

Applying one or more coatings to the gun barrel liner 50 may furthercomprise in addition to applying coating 62 or instead of coating 62cold gas-dynamic spraying the gun barrel liner 50 with a top coating 63.The top coating 63 may comprise at least one of titanium powder,titanium alloy powder, aluminum powder, aluminum alloy powder,titanium-aluminum matrix powder, chromium powder, chromium alloy powder,cobalt powder, cobalt alloy powder, copper powder, copper alloy powder,iron powder, iron alloy powder, nickel powder, nickel alloy powder, andany combination thereof. Cold gas-dynamic spraying the gun barrel liner50 with the coating 63 may comprise cold gas-dynamic spraying the gunbarrel liner 50 with the coating 63 until it is (or the coatings 62 and63 together if coating 62 is included) is/are between approximately0.300 inches and 0.500 inches thick.

Various methods may comprise heat treating coatings 62 and 63 or coating63, spraying coating 63 with a ceramic coating before sealing coating 63with the liquid metal sealer 64, contouring coating 63, sealing coating63 with a liquid metal sealer 64, and/or polishing at least one ofcoating 62 and coating 63.

As explained previously, heat treating coatings typically comprises heattreating or annealing the respective coating(s) at applicabletemperatures to normalize the material as applied. Heat treatmenttemperature ranges may be between approximately −300° C. and 1500° C.According to various aspects, heat treating of the one or more coatingsmay be performed after machining of the coatings or, alternatively,after an initial machining and before a final machining of the coatings.

Contouring an applied or sprayed layer may comprise machining, grinding,or any other method of contouring otherwise known in the art. In one ormore implementations, the layer on the fabricated gun barrel iscontoured to a specified barrel contour.

Polishing a layer is typically performed after the layer is contoured.Sand paper comprising between approximately 100 and 800 grit may beutilized to polish the fabricated gun barrel.

According to some aspects, a ceramic top coating may be applied to anouter coating of the fabricated gun barrel before the gun barrel issealed with a seal coating. The ceramic top coating typically addsaesthetic and mechanical properties, such as vibration and heat control,to the gun barrel. The ceramic top coating may be applied to a desiredthickness. In one or more implementations, the ceramic top coating isapplied to a thickness of between approximately 0.015 inches and 0.030inches. Application of the ceramic top coating may be through anyapplication method or mechanism known in the art. In one, non-limitingimplementation, the ceramic top coating is applied by plasma flamespraying the ceramic top coating on the fabricated gun barrel.

According to some aspects, sealing the fabricated gun barrel comprisesseal coating the exterior of the outer coating of the fabricated gunbarrel with a liquid metal sealer. The liquid metal sealer may be of aphenolic base, such as those liquid metal sealers supplied by Metco(Metcoseal AP or BP) or Dictol Sealer. In other implementations, anyliquid metal sealer known in the art may be utilized.

In general, any references to spraying in this document may comprisethermal spraying techniques and be employed to apply at least one coat.In one or more implementations, a single coat may comprise a bond coator a top coat, such as a metallic coating or other applicable coating.If two coats are applied to some implementations, the coats may comprisea bond coat and a top coat (such as a ceramic coating or otherapplicable coating). The top and bond coats may be distinct andseparate. Alternatively, they may comprise a graduated coat whichtransitions from only a bond coat to an integrated bond/top coat (e.g.,metal with alloy, metal with metal, metal with ceramic, and the like) toonly a top coat.

It is further noted that any of the sprayed coatings may be comprised ofmetal, ceramic, alloys, superalloys, and combinations of thereof.Plastics and polymer materials may also be included as all or part ofany of the coatings described herein. These coatings will enhance thefirearms and their parts for accuracy, longevity, accuracy and grip.

Thermal spray is used in its broadest sense and, for the exemplarypurposes of this disclosure, may include Plasma Flame Spray, Twin WireArc Spray, Combustion Powder or Wire Spray, Low Pressure Cold Spray,High Pressure Cold Spray, Low Pressure or Vacuum Plasma Spray would beused. Other coatings that may be used are CVD (Chemical VaporDeposition), PVD (Physical Vapor Deposition), Thin film coatingprocesses, Sputtering, and the like.

Specifically and for the exemplary purposes of this disclosure, barrelsmay be simply prepared and sprayed to a thickness of about 0.015-0.030″for example for a coating barrel enhancement. Alternatively, the barrelmay be a midweight or lightweight barrel, or if it is a heavier barrel,pre-machined to remove major material (about 0.100-0.250″ for example),and then a very thick coating of about 0.100-0.250″ for example may beapplied. Pre-machining and “thin walling” the barrel, or any othersuitable firearm part for that matter, allows the coating thickness tomaintain its maximum benefit or purpose. This in turn allows a lightercomponent with greater strength and accuracy potential than normalmanufacturing techniques. Pre-machining and “thin walling” include butare not be limited to machining, grinding, EDM, hand finishing, and/orthe like before and/or after spray coating is applied.

From a preparation standpoint, firearm barrels may have holes,scratches, wording, or other defects or issues that need to be repaired,filled, covered up, and the like before applying the coat. This may beaccomplished by spraying a coat (using a Cold Spray process for example)over the particular area at issue.

It will be understood that implementations are not limited to thespecific components and steps disclosed herein, as virtually anycomponents and steps consistent with the intended gun barrelmanufacturing implementation may be utilized. Accordingly, for example,although particular components, steps, and so forth, are disclosed, suchsteps may employ components of any shape, size, style, type, model,version, class, grade, measurement, concentration, material, weight,quantity, and/or the like consistent with the intended operation of agun barrel manufacturing implementation. Implementations are not limitedto uses of any specific components, provided that the componentsselected are consistent with the intended gun barrel manufacturingimplementation.

Various gun barrel implementations may be manufactured usingconventional procedures as added to and improved upon through theprocedures described here. It will also be understood that thefabricating of gun barrel implementations are not limited to thespecific order of steps as disclosed in this document. Any steps orsequence of steps of the fabricating of gun barrel implementationsindicated herein are given as examples of possible steps or sequence ofsteps and not as limitations, since various fabricating processes andsequences of steps may be used to fabricate gun barrel implementations.

Implementations of the disclosures presented herein are particularlyuseful in enhancing and improving weapon accuracy, handling, andappearance. Implementations may also be used in a variety ofapplications with similar results, such as military, shooting sportscompetition, hunting, and personal firearm applications. However,implementations are not limited to these uses. Implementations of theforegoing and other aspects and implementations may have one or more orall of the following advantages. They will enhance the performance offirearms. Barrels will have temperature control, harmonic balance, andcorrosion protection. In addition, barrels will be or have one or moreor all of the following: a pleasing aesthetic appearance; dull, lowshine light reflection; reduced weight; harder and more durable andscratch resistant; and/or longer lasting.

Also contemplated as part of this disclosure is spray coating of firearmparts and component in addition to the barrel. For example, a triggerspray may by applied to the finger face about a 0.015-0.030″ thick coatto add “grip control” for a non-slip surface for good to extremeconditions. A sear spray may be applied on the engagement surface to addlongevity, positive disengagement, and a hard, lasting, lubricationcoating for maximum release control. For example, a tungsten carbidecoat may be applied which provides a harder wear surface than theoriginal metal and which may be polished and can retain its polishedstate longer than the original metal. A bushing spray may be applied notonly to the barrel using a metallic/ceramic material, but also machiningabout 0.010 inch off the barrel seat face and applying aluminum via acold spray process for example. Aluminum has different properties thansteel and is used as a vibration dampening material interfacing with theaction. In this manner a metallurgical bonded aluminum bushing may beformed between the barrel and action. The metallurgical bonded aluminumbushing may be machined to meet “head space” dimensions for the caliberused. A preparation spray may be applied to firearm parts having holes,scratches, wording, or other defects or issues that need to be repaired,filled, covered up, and the like before applying the coat. This may beaccomplished by spraying a coat (using a cold spray process for example)over the particular area at issue.

In places where the description above refers to particularimplementations, it should be readily apparent that a number ofmodifications may be made without departing from the spirit thereof andthat these implementations may be applied to other applications. Thepresently disclosed implementations are, therefore, to be considered inall respects as illustrative and not restrictive.

It will also be understood that implementations are not limited to thespecific components disclosed herein, as virtually any componentsconsistent with the intended operation of a method and/or systemimplementation for gun barrel manufacturing may be utilized.Accordingly, for example, although particular gun barrels, gun barrelliners, and other components may be disclosed, such components maycomprise any shape, size, style, type, model, version, class, grade,measurement, concentration, material, weight, quantity, and/or the likeconsistent with the intended operation of a method and/or systemimplementation for a gun barrel may be used.

In places where the description above refers to particularimplementations of gun barrel manufacturing, it should be readilyapparent that a number of modifications may be made without departingfrom the spirit thereof and that these implementations may be applied toother methods of manufacturing a gun barrel. The accompanying claims areintended to cover such modifications as would fall within the truespirit and scope of the disclosure set forth in this document. Thepresently disclosed implementations are, therefore, to be considered inall respects as illustrative and not restrictive, the scope of thedisclosure being indicated by the appended claims rather than theforegoing description. All changes that come within the meaning of andrange of equivalency of the claims are intended to be embraced therein.

The invention claimed is:
 1. A method of manufacturing a gun barrelcomprising: cold gas-dynamic spraying a mandrel comprising rifling witha first coating comprising at least one of tungsten carbide, chromecarbide, ceramic, and any combination thereof; and cold gas-dynamicspraying the mandrel with a second coating after cold gas-dynamicspraying the first coating, the second coating comprising at least oneof a nickel based alloy or, a nickel-chromium based alloy or superalloy,and a cobalt based alloy or superalloy.
 2. The method of claim 1,wherein cold gas-dynamic spraying a mandrel with a first coating resultsin a coating thickness of between approximately 0.005 inches and 0.010inches.
 3. The method of claim 1, wherein cold gas-dynamic spraying themandrel with a second coating results in a coating thickness of betweenapproximately 0.050 inches and 0.100 inches.
 4. The method of claim 1,further comprising heat treating the first and second coatings.
 5. Themethod of claim 1, further comprising cold gas-dynamic spraying themandrel with a third coating comprising at least one of titanium powder,titanium alloy powder, aluminum powder, aluminum alloy powder,titanium-aluminum matrix powder, chromium powder, chromium alloy powder,cobalt powder, cobalt alloy powder, copper powder, copper alloy powder,iron powder, iron alloy powder, nickel powder, nickel alloy powder, andany combination thereof.
 6. The method of claim 4, wherein coldgas-dynamic spraying the mandrel with a third coating results in acombined coating thickness for the first, second, and third coatings ofbetween approximately 0.250 inches and 0.500 inches.
 7. The method ofclaim 4, further comprising heat treating the first, second, and thirdcoatings.
 8. A method of manufacturing a gun barrel comprising: coldgas-dynamic spraying a mandrel comprising rifling with a first coatingcomprising at least one of an alloy, a superalloy, and any combinationthereof.
 9. The method of claim 8, wherein cold gas-dynamic spraying amandrel with a first coating comprises cold gas-dynamic spraying themandrel with a coating comprising one of a nickel based, nickel-chromiumbased, and cobalt based alloy or superalloy.
 10. The method of claim 8,wherein cold gas-dynamic spraying a mandrel with a first coating resultsin a coating thickness of between approximately 0.050 inches and 0.100inches.
 11. The method of claim 8, further comprising heat treating thecoating.
 12. The method of claim 8, further comprising cold gas-dynamicspraying the mandrel with a second coating comprising at least one oftitanium powder, titanium alloy powder, aluminum powder, aluminum alloypowder, titanium-aluminum matrix powder, chromium powder, chromium alloypowder, cobalt powder, cobalt alloy powder, copper powder, copper alloypowder, iron powder, iron alloy powder, nickel powder, nickel alloypowder, and any combination thereof.
 13. The method of claim 12, whereincold gas-dynamic spraying the mandrel with a second coating results in acombined coating thickness for the first and second coatings of betweenapproximately 0.250 inches and 0.500 inches.
 14. The method of claim 12,further comprising heat treating the first and second coatings.
 15. Amethod of manufacturing a gun barrel comprising: cold gas-dynamicspraying a mandrel with an initial coating comprising at least one oftungsten carbide, chrome carbide, ceramic, and any combination thereof;and cold gas-dynamic spraying the mandrel with a second coatingcomprising at least one of titanium powder, titanium alloy powder,aluminum powder, aluminum alloy powder, titanium-aluminum matrix powder,chromium powder, chromium alloy powder, cobalt powder, cobalt alloypowder, copper powder, copper alloy powder, iron powder, iron alloypowder, nickel powder, nickel alloy powder, and any combination thereof.16. The method of claim 15, wherein cold gas-dynamic spraying themandrel with a coating results in a coating thickness of betweenapproximately 0.250 inches and 0.500 inches.
 17. The method of claim 15,further comprising heat treating the first and second coatings.
 18. Themethod of claim 15, further comprising cold gas-dynamic spraying themandrel wherein the mandrel comprises rifling.
 19. The method of claim18, wherein cold gas-dynamic spraying the mandrel with the initialcoating results in a coating thickness of between approximately 0.005inches and 0.010 inches.